1. Field of the Invention
The present invention generally relates to a copying apparatus, and more particularly to a copying apparatus which is capable of automatically selecting a size of a copy paper sheet.
2. Description of the Related Art
Conventionally, there are provided copying machines which are capable of carrying out a copying operation at a desirable magnification ratio which is selected out of a plurality of available magnification ratios which are predeterminedly fixed. The fixed magnification ratios, for example, may be 0.707-magnification, 0.865-magnification and 1.414-magnification. These magnifications are determined so as to correspond to enlargement and/or reduction between regular-sized sheets. That is, 0.707-magnification is applied to reduction from A3-size to A4-size(at longitudinal position), 0.865-magnification is applied to reduction from A3-size to B4-size( at longitudinal position ), and 1.414-magnification is applied to enlargement from A4-size (at longitudinal position) to A3-size.
As described above, the magnification ratio of ".times.0.707" corresponds to a reduction-copying between the A3-sized and A4-sized regular sheets. Therefore, the magnification ratio of "0.707" is usually selected, assuming that the reduction from A3-size to A4-size at its longitudinal position is performed. To this end, the copying machine automatically selects the A4-sized copy paper sheet which is positioned longitudinally in case where the magnification ratio of "0.707" is selected.
The above-mentioned disadvantage is caused at selection of another copying mode as well as at the selection of the magnification. For example, when a copying mode of copying from two originals on a document platen to an individual copy paper sheet (it is a so-called book mode) is performed, it is necessary for some users to take an action for selecting the A4-sized sheet positioned sideways in addition to taking an action for the selection of the copying mode every time the book mode is selected, nevertheless they always use the A4-sized sheet positioned lengthwise. Furthermore, in an edition mode representative of copying an only image of an optional area which is assigned in the original, it is necessary to select the copy paper sheet having the size suitable for copying the image of the fixed area every time the area is fixed.